Method instanceOf

packages/tinytest/tinytest.js:159–164

(obj, klass, message)

  }

  instanceOf(obj, klass, message) {
    if (obj instanceof klass)
      this.ok();
    else
      this.fail({type: "instanceOf", message: message, not: false}); // XXX what other data?
  }

  notInstanceOf(obj, klass, message) {
    if (obj instanceof klass)